304 PHILOSOPHICAL TRANSACTIONS. [aNNO 1792. 



known, will to a certain degree deaden, or indeed prevent the sensation of cold ; 

 and what does this I apprehend prevents, or at least weakens, its physical action. 

 The astronomer, intent on the objects of his sublime science, it is said, neither 

 feels, nor is injured by, the damps nor the chillness of the night ; and in some 

 species of madness, where the ideas of imagination are too vivid to admit the im- 

 pressions of sense, cold is resisted to an extraordinary degree. I have seen a 

 young woman, once of the greatest delicacy of frame, struck with madness, lie 

 all night on a cold floor, with hardly the covering that decency requires, when 

 the water was frozen on the table by her, and the milk that she was to feed on was 

 a mass of ice. 



7. There are particular conditions of the atmosphere, not perfectly understood, 

 that seem to have an influence in depriving us more speedily of our animal heat, 

 than others where the cold is greater. 



It may seem that by this time I had renounced my intention of trying the 

 effects of immersion in fresh water on the animal powers, and particularly on the 

 heat. Some trials I have, however, made, of which I shall only relate the fol- 

 lowing. 



Exper. 10. In the same vessel, containing an equal bulk of fresh water. Rich. 

 Edwards, the subject of my first experiments, was immersed, at the same hour 

 of the day. His heat previously was 98°, his pulse beat 92 in the minute : the 

 heat of the air was 414-°, that of the water 40°. The wind was now in the west, 

 -so that in the court where the bath stood there was a perfect calm. As I had 

 some fears of the issue of this experiment, instead of exposing him for a minute 

 naked to the wind before immersion, he was covered with a flannel dress from the 

 air till the instant he descended into the water, into which he was suffered to sink 

 himself slowly, with the bulb of the thermometer under his tongue. These are 

 important circumstances. The following table exhibits the result. 



Immediately on immersion heat .... 98° 



1 minute after 97h 



2 minutes 97 



3 98 



4 97h 



5 96 



6 96 



7, 8 96 



9 97 



10 97 



11, 12, 13 00 



14. minutes after, heat 96}^° 



15 96 



16, 17, 18, 19, 20 96 



21, 22, 23, 24 00 



25 95 



26" 94 



27 93^ 



28. 29 94 



30 93 



31, 32 94 



33, 34 92 J 



He now got out into the air very slowly, and stood in it 3"\ the wind not 

 blowing on him. He lost 1° of heat at first, which he recovered. He was then 

 put into a warm bath at 90°, which at first he felt warm, and his feet and hands 

 were pained : but in 9."" he fell into a very violent shiver, and his heat fell 2°. The 



